1 // Safe container implementation -*- C++ -*- 2 3 // Copyright (C) 2014-2022 Free Software Foundation, Inc. 4 // 5 // This file is part of the GNU ISO C++ Library. This library is free 6 // software; you can redistribute it and/or modify it under the 7 // terms of the GNU General Public License as published by the 8 // Free Software Foundation; either version 3, or (at your option) 9 // any later version. 10 11 // This library is distributed in the hope that it will be useful, 12 // but WITHOUT ANY WARRANTY; without even the implied warranty of 13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 // GNU General Public License for more details. 15 16 // Under Section 7 of GPL version 3, you are granted additional 17 // permissions described in the GCC Runtime Library Exception, version 18 // 3.1, as published by the Free Software Foundation. 19 20 // You should have received a copy of the GNU General Public License and 21 // a copy of the GCC Runtime Library Exception along with this program; 22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 23 // <http://www.gnu.org/licenses/>. 24 25 /** @file debug/safe_container.h 26 * This file is a GNU debug extension to the Standard C++ Library. 27 */ 28 29 #ifndef _GLIBCXX_DEBUG_SAFE_CONTAINER_H 30 #define _GLIBCXX_DEBUG_SAFE_CONTAINER_H 1 31 32 #include <ext/alloc_traits.h> 33 34 namespace __gnu_debug 35 { 36 /// Safe class dealing with some allocator dependent operations. 37 template<typename _SafeContainer, 38 typename _Alloc, 39 template<typename> class _SafeBase, 40 bool _IsCxx11AllocatorAware = true> 41 class _Safe_container 42 : public _SafeBase<_SafeContainer> 43 { 44 typedef _SafeBase<_SafeContainer> _Base; 45 46 _SafeContainer& _M_cont()47 _M_cont() _GLIBCXX_NOEXCEPT 48 { return *static_cast<_SafeContainer*>(this); } 49 50 protected: 51 #if __cplusplus >= 201103L 52 _Safe_container() = default; 53 _Safe_container(const _Safe_container&) = default; 54 _Safe_container(_Safe_container&&) = default; 55 56 private: _Safe_container(_Safe_container && __x,const _Alloc &,std::true_type)57 _Safe_container(_Safe_container&& __x, const _Alloc&, std::true_type) 58 : _Safe_container(std::move(__x)) 59 { } 60 _Safe_container(_Safe_container && __x,const _Alloc & __a,std::false_type)61 _Safe_container(_Safe_container&& __x, const _Alloc& __a, std::false_type) 62 : _Safe_container() 63 { 64 if (__x._M_cont().get_allocator() == __a) 65 _Base::_M_swap(__x); 66 else 67 __x._M_invalidate_all(); 68 } 69 70 protected: _Safe_container(_Safe_container && __x,const _Alloc & __a)71 _Safe_container(_Safe_container&& __x, const _Alloc& __a) 72 : _Safe_container(std::move(__x), __a, 73 typename std::allocator_traits<_Alloc>::is_always_equal{}) 74 { } 75 #endif 76 77 // Copy assignment invalidate all iterators. 78 _Safe_container& 79 operator=(const _Safe_container&) _GLIBCXX_NOEXCEPT 80 { 81 this->_M_invalidate_all(); 82 return *this; 83 } 84 85 #if __cplusplus >= 201103L 86 _Safe_container& 87 operator=(_Safe_container&& __x) noexcept 88 { 89 if (std::__addressof(__x) == this) 90 { 91 // Standard containers have a valid but unspecified value after 92 // self-move, so we invalidate all debug iterators even if the 93 // underlying container happens to preserve its contents. 94 this->_M_invalidate_all(); 95 return *this; 96 } 97 98 if (_IsCxx11AllocatorAware) 99 { 100 typedef __gnu_cxx::__alloc_traits<_Alloc> _Alloc_traits; 101 102 bool __xfer_memory = _Alloc_traits::_S_propagate_on_move_assign() 103 || _M_cont().get_allocator() == __x._M_cont().get_allocator(); 104 if (__xfer_memory) 105 _Base::_M_swap(__x); 106 else 107 this->_M_invalidate_all(); 108 } 109 else 110 _Base::_M_swap(__x); 111 112 __x._M_invalidate_all(); 113 return *this; 114 } 115 116 void _M_swap(_Safe_container & __x)117 _M_swap(_Safe_container& __x) noexcept 118 { 119 if (_IsCxx11AllocatorAware) 120 { 121 typedef __gnu_cxx::__alloc_traits<_Alloc> _Alloc_traits; 122 123 if (!_Alloc_traits::_S_propagate_on_swap()) 124 __glibcxx_check_equal_allocs(this->_M_cont()._M_base(), 125 __x._M_cont()._M_base()); 126 } 127 128 _Base::_M_swap(__x); 129 } 130 #endif 131 }; 132 133 } // namespace __gnu_debug 134 135 #endif 136